Smoking during pregnancy: association with childhood temperament, behavior, and academic performance

The effect of maternal prenatal tobacco smoking on offspring academic achievement: A systematic review and meta-analysis

BACKGROUND

Previous epidemiological studies examining the prospective association between maternal prenatal tobacco smoking and offspring academic achievement have reported conflicting results. Therefore, this systematic review and meta-analysis was conducted to examine the magnitude and consistency of association reported by those studies.

METHODS

This systematic review and meta-analysis was guided by the PRISMA protocol. Relevant epidemiological studies on the topic were extracted from four main databases (PubMed/Medline, Embase, PsycINFO, and Scopus). The Newcastle-Ottawa Scale (NOS) was used to appraise the methodological quality of the included studies. We conducted a narrative assessment of the studies that did not report effect estimates. Inverse variance-weighted random effect meta-analysis was used to combine studies reporting effect sizes to estimate pooled adjusted odds ratio with 95% confidence intervals (95% CI). The review was prospectively registered in PROSPERO (CRD42022350901).

RESULTS

Nineteen observational studies, published between 1973 and 2021 with a total of 1.25 million study participants were included in the final review. Of these, fifteen studies (79 %) reported reduced academic achievement in offspring exposed to maternal prenatal tobacco smoking. The eight primary studies (sample size = 723,877) included in the meta-analysis together suggested a 49 % higher risk of reduced academic achievement in offspring exposed to maternal prenatal tobacco smoking when compared to non-exposed offspring (Pooled odds ratio = 1.49, 95 % CI:1.17-1.91).

CONCLUSION

Our review found a positive association between maternal prenatal tobacco smoking and offspring reduced academic achievement. However, variation in the adjustment of potential confounders and significant heterogeneity across included studies limited more conclusive inference. Mechanistic studies to identify causal pathways and specific academic impacts are needed to inform targeted developmental programs to assist child learning and academic performance.

Long-term impact of tobacco exposure during pregnancy on children's psychomotor development

BACKGROUND

Both active and second-hand smoking (SHS) can cause complications during pregnancy and after delivery. This study aimed to assess how tobacco exposure (active and passive) during the fetal period could impact the psychomotor development of children when they attain the age of 3-6 years.

METHODS

The study included 160 mothers and their 3-6 year-old children. Two research groups were set up of children born to active or SHS mothers during the period when they were pregnant and a control group of children of non-smoking mothers. The parameters of the psychomotor development of the children were measured using the Age & Stage Questionnaires 3® (ASQ-3).

RESULTS

Children, whose mothers were smokers themselves or who were exposed to SHS during the period of pregnancy had an average psychomotor development score of 221 points versus 243.5 points in the control group. Twenty-six percent had delays (near or under the cut-off scores) in one of the assessed psychomotor areas and 60% had two or more psychomotor delays; 36% of children whose mothers were not exposed to smoking during pregnancy had normal psychomotor development and only 34% presented multiple psychomotor delays.

CONCLUSIONS

Fetuses exposed to tobacco are more likely to achieve a psychomotor development in the 'monitor' and 'fail' areas compared to the non-exposed control group. The children exposed to smoking during their fetal development should be considered as a group at risk of developmental delays, therefore they should be closely monitored and supported by caregivers and developmental pediatricians.

Associations between antenatal maternal diet and other health aspects with infant temperament in a large multiethnic cohort study: a path analysis approach

OBJECTIVES

The aim of this study was to assess the association of antenatal maternal dietary patterns (DPs) and other health aspects with infant temperament in a large multiethnic cohort, taking maternal personality and prenatal stress into account.

DESIGN AND METHODS

Using data from 3968 children born in 2009/2010 and their mothers from the Growing Up in New Zealand cohort, infant temperament was assessed at 9 months using the Infant Behavior Questionnaire-Revised Very Short Form. Maternal antenatal diet and other health aspects were assessed antenatally. Maternal DPs (n=4) were derived using principal components analysis based on food intake reported on a 44-item food frequency questionnaire. Path analyses investigated factors associated with infant temperament, namely maternal personality, prenatal maternal stress, DPs and other health aspects, including potential inter-relations and mediating effects.

RESULTS

Women who scored higher in the fusion DP (standardised beta (β)=0.05; 95% CI 0.02 to 0.09) and healthy DP (β=0.05; 95% CI 0.02 to 0.09), who exercised more (β=0.04; 95% CI 0.01 to 0.07), and who drank less alcohol (β=-0.05; 95% CI -0.08 to -0.02) were more likely to have infants with an overall less difficult temperament. Sex-specific differences were found in the associations between maternal DP and infant temperament. Maternal personality and prenatal stress were significantly associated with all dimensions of infant temperament. The strongest predictors for a more difficult temperament were prenatal stress (β=0.12; 95% CI 0.08 to 0.15) and the personality dimensions neuroticism (β=0.10; 95% CI 0.07 to 0.14) and extraversion (β=-0.09; 95% CI -0.12 to -0.06).

CONCLUSIONS

Associations of antenatal maternal diet and health aspects with infant temperament were statistically significant but small. While they should not be overinterpreted as being deterministic, the findings of this study support the link between maternal modifiable health-related behaviours and infant temperament outcomes.

Maternal smoking during pregnancy and poor academic performance in adolescent offspring: A registry data-based cohort study

BACKGROUND

Previous studies have suggested associations between maternal smoking during pregnancy (MSDP) and a range of adverse outcomes in offspring. However, evidence reporting adverse effects on poor academic performance in adolescence is scant.

METHODS

This register-based cohort study used linked data obtained from New South Wales (NSW) educational and health registries in Australia. MSDP was assessed using self-reports of smoking during pregnancy. Offspring's educational performance was assessed using the National Assessment Program for Literacy and numeracy (NAPLAN), when students were in grade 9 and approximately aged 14 years. We used multivariable logistic regression models to explore associations.

RESULTS

Adolescent offspring exposed to MSDP were at an increased risk of substandard academic performance in all domains, with the highest odds for spelling [OR, 3.12 (95%CI 2.98-3.26)] followed by writing [OR, 2.97 (95%CI 2.84-3.11)], reading [OR, 2.49 (95%CI 2.37-2.62)], and numeracy [OR, 2.43 (95%CI 2.30-2.58)]. In our sex-stratified analysis, MSDP displayed stronger effects on the academic performance of female offspring in all domains.

CONCLUSIONS

Our findings showed that MSDP was associated with an increased risk of reduced academic performance in adolescent offspring. The different effects of MSDP on the academic performance of male and female offspring is a new finding, which needs further investigation.

Decreased head circumference at birth associated with maternal tobacco smoke exposure during pregnancy on the Japanese prospective birth cohort study

Maternal tobacco smoke exposure during pregnancy impairs fetal body size, including head circumference (HC) at birth; however, the mechanism still remains unclear. This analysis using a large prospective cohort study evaluated the impact of maternal tobacco exposure on their offspring's HC and the relationship with placental weight ratio (PWR) and placental abnormalities. Parents-children pairs (n = 84,856) were included from the 104,065 records of the Japan Environmental and Children's Study. Maternal perinatal clinical and social information by self-administered questionnaires, offspring's body size, and placental information were collected. Data were analyzed with binominal logistic regression analysis and path analysis. Logistic regression showed significantly elevated adjusted odds ratio (aOR) (1.653, 95% CI 1.387-1.969) for the impact of maternal smoking during pregnancy on their offspring's smaller HC at birth. Maternal exposure to environmental tobacco smoke in the non-smoking group did not increase aOR for the smaller HC. Path analysis showed that maternal smoking during pregnancy decreased the offspring's HC directly, but not indirectly via PWR or placental abnormalities. The quitting smoking during pregnancy group did not increase aOR for the smaller HC than the non-smoking group, suggesting that quitting smoking may reduce their offspring's neurological impairment even after pregnancy.

A sibling-comparison study of smoking during pregnancy and risk for reading-related problems

This research examines the relationship between smoking during pregnancy (SDP) and risk for reading related problems in siblings discordant for exposure to SDP. Data (N = 173 families) were drawn from the Missouri Mothers and Their Children study, a sample, identified using birth records (years 1998-2005), in which mothers changed her smoking behavior between two pregnancies (Child 1 [older sibling]: M = 12.99; Child 2 [younger sibling]: M = 10.19). A sibling comparison approach was used, providing a robust test for the association between SDP and reading related outcomes in school-aged children. Results suggested within-family (i.e., potentially causal) associations between SDP and reading and language/comprehension factor scores, as well as between SDP and specific reading-related skills, including reading accuracy and receptive language, with increased exposure to SDP associated with decreased performance. SDP was not associated with spelling, reading rate, or receptive vocabulary. Initial within-family associations between SDP and word-letter identification, phonetic/decoding skills, and reading comprehension were fully attenuated following partial control for genetic and environmental confounding of the associations. These findings indicate that exposure to SDP is associated with poorer performance on some, but not all skills assessed.

Prenatal and Intrapartum Factors Associated With Infant Temperament: A Systematic Review

Background: Temperament involves individual variations in behavioural tendencies of emotional responses and reactions to stimuli after birth. Because 'foetal programming' is a strong hypothesis in developing temperament, prenatal and intrapartum factors may be significant determinants of infant temperament. This systematic literature review aims to elucidate the evidence of prenatal and intrapartum predictors, including genetic, biological, environmental, socio-demographic, psychological, and obstetric factors of parents and their child. Methods: Relevant articles were searched using MEDLINE, PubMed, and SCOPUS. The inclusion criteria were (a) original research article, (b) written in English, (c) assessed the temperament of infants 12 months old or younger as an outcome variable, and (d) investigated prenatal and intrapartum factorial variables of infant temperament. Following the PRISMA guideline, the articles found in the three databases were screened and selected according to the inclusion and exclusion criteria before the final review. Results: Finally, 35 articles were reviewed. This systematic review identified a variety of prenatal and intrapartum factors that were significantly associated with infant temperament: (1) genetic and biological factors: certain genotypes, maternal cortisol and ACTH, and CRHs, (2) environmental factors: substance use such as tobacco, alcohol, and illegal drugs, (3) socio-demographic factor: lower-income, (4) psychological factors: depression or anxiety, eating disorders, personality types of mothers, and domestic violence, and (5) obstetric factors: foetal growth (birth weight), hypertension in mothers, nausea (emesis), and preterm birth. Conclusion: The findings support gene-environment interaction and biological mechanisms for developing infant temperament, suggesting the importance of ensuring a safe and comfortable environment for pregnant mothers, unborn infants, and families during pregnancy and delivery.

Low Birth Weight and Psychoeducational Outcomes: Investigation of an African American Birth Cohort

African Americans experience more than double the prevalence of low birth weight (LBW)/premature birth compared to their Caucasian counterparts, reflecting a public health crisis and a significant social justice concern. However, there is a paucity of LBW outcome studies in African American samples. There are even fewer that investigate developmental outcomes within the moderately LBW range (i.e., 1500–2500 g), the most prevalent category of LBW births. This study investigates the relationship between LBW and various psychoeducational outcomes in a prospectively designed African American birth cohort. Multivariate logit analyses of the Johns Hopkins University Pathways to Adulthood study compared LBW children with normal birth weight children on a number of outcome measures at seven and 8 years of age. Results revealed that children born within the lowest birth weight category produced the most adverse findings, from both a statistical and clinical standpoint, on measures of cognitive ability, academic achievement, speech, language, auditory processing, and visual–motor integration.

Maternal cigarette use during pregnancy and school readiness: An analysis of preschool age children in São Paulo, Brazil

BACKGROUND

Barriers to early childhood development (ECD) are a global concern. Limited research exists on prenatal smoking and ECD in vulnerable populations, especially as it relates to school readiness (SR).

AIMS

To examine how maternal cigarette use during pregnancy is associated with SR in a sample of Brazilian preschool-age children.

STUDY DESIGN

We used the Brazilian Preschool Mental Health Study, a cross-sectional, epidemiological study of preschool-age children in Embu das Artes, São Paulo. SR was assessed using the Engle Scale of Child Development (ESCD). We restricted analyses to biological mothers, who represented 81.9% (n = 591) of the total 722 with ESCD data. Logistic regression models, adjusting for birth and child characteristics (year of preschool, sex, race, history of head trauma, coma, convulsions or epilepsy), sociodemographic factors and school environment, were used to estimate odds ratios and 95% confidence intervals.

RESULTS

Prenatal smoking was negatively associated with SR. Children of mothers who smoked during pregnancy were more likely to be in the lowest ESCD quartile (aOR = 1.26, 95%CI: [1.02-1.55]) compared to those of non-smoking mothers, and each cigarette resulted in additional risk (aOR = 1.03, 95%CI:[1.01-1.05]). Children of heavy smokers had worse ESCD scores compared to children of non-smokers (aOR = 1.69, 95%CI:[1.18-2.44]), as well as when compared to children of moderate and non-smokers combined (aOR = 1.77, 95%CI:[1.22-2.57]). This relationship was not seen when comparing children of moderate smokers to children of non-smokers. Inferences were robust when examining very heavy smoking.

CONCLUSION

Maternal tobacco use during pregnancy may affect child SR. Additional studies in other populations are needed to corroborate these results.

[In Utero Exposure to Maternal Smoking: Impact on the Child from Birth to Adulthood - CNGOF-SFT Expert Report and Guidelines for Smoking Management during Pregnancy]

INTRODUCTION

Smoking during pregnancy leads to fetal passive smoking. It is associated with several obstetrical complications and is a major modifiable factor of maternal and fetal morbidity. Long-term consequences also exist but are less well known to health professionals and in the general population.

METHODS

Consultation of the Medline® database.

RESULTS

Maternal smoking during pregnancy is associated in the offspring with sudden infant death syndrome (NP2), impaired lung function (NP2), lower respiratory infections and asthma (NP2), overweight and obesity (NP2), cancers (NP3), risk of tobacco use, nicotine dependence and early smoking initiation (NP2). Unadjusted analyses show associations between in utero tobacco exposure and cognitive deficits (NP3), impaired school performance (NP3) and behavioral disorders in children (NP2), which are in a large part explained by environmental factors. There is a cross-generational effect of smoking during pregnancy. For example, an increased risk of asthma is observed in the grandchildren of smoking women (NP4). The respective roles of ante- and post-natal smoking remain difficult to assess.

CONCLUSION

These results highlight the importance of prevention measures against tobacco use in the general population, as well as screening measures and support for smoking cessation before or at the beginning of the pregnancy.

Drinking or Smoking While Breastfeeding and Later Academic Outcomes in Children

Alcohol consumed by breastfeeding mothers has been associated with reduced grammatical comprehension and cognition in children. This study examined whether drinking or smoking while breastfeeding was associated with reductions in Australian National Assessment Program–Literacy and Numeracy assessments. Data was sourced from The Growing Up in Australia Study. This is an ongoing longitudinal study of 5107 infants and mothers recruited in 2004 and followed over time every two years. Multivariable linear regression found that maternal alcohol consumption at study entry was associated with reductions in Grade 3 (age 7–10 years) National Assessment Program–Literacy and Numeracy writing (b = −1.56, 95% CI: −2.52; −0.60, p = 0.01), spelling (b = −2.06, 95% CI: −3.31; −0.81, p < 0.0001) and grammar and punctuation (b = −2.11, 95% CI: −3.59; −0.64, p = 0.01) scores, as well as Grade 5 (age 9–11 years) spelling scores (b = −1.58, 95% CI: −2.74; −0.43, p = 0.03) in children who had been breastfed at any time. This was not evident in babies who had never breastfed, or in the smaller group of infants who were actively breastfeeding at study entry. Smoking was not associated with any outcome variable. Drinking alcohol while breastfeeding may result in dose-dependent reductions in children’s academic abilities. While reductions are small, they may be of clinical significance if mothers drink large quantities. Further analyses are planned to assess developmental, physical and behavioural outcomes in children.

Placental Gene Expression and Offspring Temperament Trajectories: Predicting Negative Affect in Early Childhood

Exposure to prenatal stress increases offspring risk for long-term neurobehavioral impairments and psychopathology, such as Attention Deficit Hyperactivity Disorder (ADHD). Epigenetic regulation of glucocorticoid pathway genes may be a potential underlying mechanism by which maternal conditions 'program' the fetal brain for downstream vulnerabilities. The present study aims to investigate whether mRNA expression of glucocorticoid pathway genes in the placenta predict offspring negative affect during early childhood (between 6 and 24 months). Participants include 318 mother-child dyads participating in a longitudinal birth cohort study. Placental mRNA expression of glucocorticoid pathway genes (HSD11B1, HSD11B2, NR3C1, NCOR2) were profiled and negative affect traits of the offspring were measured at 6, 12, 18, and 24 months. HSD11B1 mRNA expression significantly predicted negative affect (β = -.09, SE = .04; p = .036), and Distress to Limitations trajectories (β = -.13, SE = .06; p = .016). NCOR2 mRNA expression significantly predicted Distress to Limitations (β = .43, SE = .21; p = .047), and marginally predicted Sadness trajectories (β = .39, SE = .21; p = .068). HSD11B2 and NR3C1 did not predict trajectories of Negative Affect or subscale scores. Infant negative affect traits were assessed via maternal self-report, and deviated from linearity across follow-up. mRNA expression of glucocorticoid pathway genes in the placenta may be a potentially novel tool for early identification of infants at greater risk for elevated negative affect. Further study is needed to validate the utility of mRNA expression of glucocorticoid pathway genes in the placenta.

Does early maternal responsiveness buffer prenatal tobacco exposure effects on young children's behavioral disinhibition?

Children with prenatal tobacco exposure (PTE) exhibit early self-regulatory impairments, reflecting a life-course persistent propensity toward behavioral disinhibition. Previously, we demonstrated the protective role of parental responsiveness for reducing the risk of exposure-related disruptive behavior in adolescence. Here, we expanded this line of inquiry, examining whether responsiveness moderates the relation of PTE to a broader set of behavioral disinhibition features in early childhood and testing alternative diathesis-stress versus differential susceptibility explanatory models. PTE was assessed prospectively using interviews and bioassays in the Midwestern Infant Development Study (MIDS). Mother-child dyads (N = 276) were re-assessed at approximately 5 years of age in a preschool follow-up. We quantified maternal responsiveness and child behavioral disinhibition using a combination of directly observed activities in the lab and developmentally sensitive questionnaires. Results supported a diathesis-stress pattern. Children with PTE and less responsive mothers showed increased disruptive behavior and lower effortful control compared with children without PTE. In contrast, exposed children with more responsive mothers had self-regulatory profiles similar to their non-exposed peers. We did not observe sex differences. Findings provide greater specification of the protective role of maternal responsiveness for self-regulation in children with PTE and help clarify mechanisms that may underscore trajectories of exposure-related behavioral disinhibition.

Prenatal Exposure to Environmental Tobacco Smoke and Early Development of Children in Rural Guizhou Province, China

BACKGROUND

There is a substantial body of evidence supporting the association between maternal active smoking during pregnancy and child development, but the association between prenatal exposure to environmental tobacco smoke (ETS) and early child development has not been well documented. This cross-sectional study examines the association between prenatal exposure to ETS and the development of children in their first two years of life.

METHODS

We interviewed the primary caregivers of 446 children under two years old in rural Guizhou Province, China. Based on self-reported assessments about whether the mother was exposed to ETS during pregnancy, we divided the children into the ETS-exposed group or the non-exposed group. Sociodemographic information was collected through a questionnaire. The cognitive, language, motor, and socioemotional abilities of children were assessed using the Bayley Scales of Infant Development III (BSID-III). A multivariate linear regression model adjusting for confounding variables was used to estimate the association of interest.

RESULTS

About 60% of mothers experienced ETS exposure during pregnancy. Cognitive and language scores were lower among children in the ETS-exposed group. When adjusting for characteristics of the child, the mother, the household, and village fixed effects, prenatal exposure to ETS was associated with lower cognition scores (-3.41; 95% confidence interval (CI): -6.39 to -0.42; p = 0.03) and language scores (-3.01; 95% CI: -5.39 to -0.09; p = 0.04). Frequency of prenatal exposure to ETS was also negatively associated with language development (-0.48; 95% CI: -0.87 to -0.09; p = 0.02) before children reached two years old.

CONCLUSIONS

Prenatal exposure to ETS is negatively associated with the cognitive and language development of rural young children within their first two years of life. The government should take action to raise public awareness about the negative effects of tobacco use, with an emphasis on the protection of pregnant women and their children, in order to carry through comprehensive smoke-free laws in rural areas, while also increasing tobacco taxation.

Maternal smoking during pregnancy and academic achievement of offspring over time: A registry data-based cohort study

Few studies have assessed the cumulative impact of maternal smoking during pregnancy (MSDP) on scholastic outcomes over time. We examined the relations between MSDP and academic achievement in the 4th, 7th and 10th grades using registry data collected at birth, during the neonatal period, and at each grade level from the 2000, LIFECOURSE study birth cohort in Reykjavik, Iceland (N = 1151, girls = 49.3%). Latent growth modeling showed that MSDP influenced Icelandic achievement scores, standardized to a range from 0 to 60, at baseline (β = -0.04), and over time (β = -0.05). Likewise, MSDP was negatively associated with standardized mathematics scores at baseline (ß = -0.09) and continued to exert a negative impact on mathematics scores over time (ß = -0.08) after controlling for gender, income, cohabitation, and baseline mathematics and Icelandic achievement scores. Results provide evidence of the persistent negative impact of MSDP on academic achievement in offspring. Findings support the proposition that children whose mothers smoke during the first trimester of pregnancy are, on average, at greater risk for poor scholastic outcomes over time than children whose mothers do not smoke during their first trimester. To our knowledge, this is the first study using a longitudinal cohort design to assess whether the impacts of maternal smoking during pregnancy may persist over time. This study contributes to the current state of knowledge by providing an assessment that focuses on the impact of smoking during pregnancy on academic achievement from childhood into early adolescence.

Maternal smoking during pregnancy and scholastic achievement in childhood: evidence from the LIFECOURSE cohort study

Background

Research on the impact of maternal smoking during pregnancy (MSDP) on scholastic achievement in the offspring has shown conflicting findings. The objective of this study was to assess the impact of MSDP on scholastic achievement in a birth cohort of children in 4th, 7th and 10th grades.

Methods

We analysed data from the LIFECOURSE study, a cohort study of risk and protective factors in all children born in Reykjavik, Iceland, in the year 2000 (N = 1151, girls = 49.3%). Retrospective registry data for 2014–2015 were merged with prospective survey data that were collected in April 2016. Data on MSDP were assessed during regular antenatal visits at the end of the first trimester. Standardized academic achievement scores were obtained from official school transcripts. Data were analysed using OLS regressions that were entered in three hierarchical blocks.

Results

Children of mothers who smoked tobacco during the first trimester consistently revealed between 5% and 7% lower scores on standardized academic achievement in 4th, 7th and 10th grade (∼6–8 points on a normally distributed 120 point scale) than those of mothers who had not smoked tobacco during this period (P < 0.05). These findings held after controlling for several factors associated with the time of birth (e.g. birth weight, maternal age at birth, birth order, parental cohabitation and household income), as well as the year of scholastic assessment (parental cohabitation, household income and parental education).

Conclusions

Maternal smoking during pregnancy was negatively related to scholastic achievement in the offspring during 4th, 7th and 10th grade.

Environmental exposure and effects on health of children from a tobacco-producing region

Children may be environmentally exposed to several hazards. In order to evaluate the health of children living in a tobacco-producing region, different biomarkers of exposure and effect, as well as hematological parameters, were evaluated. Biomarkers of exposure to the following xenobiotics were assessed: pesticides, nicotine, toxic elements, and organic solvents. Oxidative damage markers malondialdehyde (MDA) and protein carbonyls (PCO), vitamin C, microalbuminuria (mALB) levels, and N-acetyl-β-D-glucosaminidase (NAG) activity were also evaluated. Peripheral blood samples and urine were collected from 40 children (6-12 years), at two different crop periods: in the beginning of pesticide applications (period 1) and in the leaf harvest (period 2). The Wilcoxon signed-rank test for paired data was used to evaluate the differences between both periods. Biomarkers of exposure cotinine in urine and blood chromium (Cr) levels were increased in period 1 when compared to period 2. Moreover, a significant reduced plasmatic activity of butyrylcholinesterase (BuChE) was observed in period 2 in relation to period 1. Blood Cr levels were above the recommended by WHO in both evaluations. The biomarkers MDA and PCO as well as the kidney dysfunction biomarker, mALB, presented levels significantly increased in period 1. Additionally, decreased lymphocytes and increased basophils were also observed. Cotinine was positively associated with PCO, and Cr was positively associated with PCO and MDA. The increased Cr levels were associated with decreased lymphocytes and increased basophils. Our findings demonstrate that children environmentally exposed to xenobiotics in rural area may present early kidney dysfunction, hematological alterations, as well as lipid and protein damages, associated with co-exposure to different xenobiotics involved in tobacco cultivation.

Developmental pathways from prenatal tobacco and stress exposure to behavioral disinhibition

Prenatal tobacco exposure (PTE) and prenatal stress exposure (PSE) both have been linked to externalizing behavior, although their effects generally have been considered in isolation. Here, we aimed to characterize the joint or interactive roles of PTE and PSE in early developmental pathways to behavioral disinhibition, a profile of cognitive and behavioral under-control that presages severe externalizing behavior. As part of a prospective, longitudinal study, 296 children were assessed at a mean age of 5 years. Exposures were assessed via repeated interviews across the prenatal period and bioassays of cotinine were obtained. Behavioral disinhibition was assessed using temperament measures in infancy, performance-based executive control tasks and measures of disruptive and inattentive behavior. PSE was associated with a higher probability of difficult temperament in infancy. Each exposure independently predicted poorer executive control at age 5 years. Difficult temperament and executive control difficulties in turn predicted elevated levels of disruptive behavior, although links from PTE and PSE to parent-reported attention problems were less robust. Children who experienced these prenatal exposures in conjunction with higher postnatal stress exposure showed the lowest executive control and highest levels of disruptive behavior. Findings highlight the compounding adverse impact of PTE and PSE on children's behavioral trajectories. Given their high concordance, prenatal health campaigns should target these exposures in tandem.

Smoking during pregnancy and psychiatric disorders in preschoolers

The overall objective of this study was to determine whether smoking during pregnancy is related to psychiatric disorders in 4-year-olds while controlling for a wide range of potential confounding variables (i.e. parental anxiety, depression, personality disorders, drug abuse, and socio-economic characteristics). Parents of a community sample of 4-year-olds (N = 995) residing in the city of Trondheim, Norway were interviewed using the Preschool Age Psychiatric Assessment, which includes information on prenatal smoking. After adjusting for potential confounding variables using the propensity score, smoking during pregnancy was found to increase the odds for attention-deficit/hyperactivity disorder (ADHD) OR = 2.59 (CI 1.5-4.34, p < 0.001), oppositional defiant disorder (ODD) OR = 2.69 (CI 1.84-3.91, p = 0.02) and comorbid OR = 2.55 (CI 1.24-5.23, p < 0.001). Prenatal smoking during pregnancy is associated with an increased risk for symptoms of ADHD and ODD independently of each other, in 4-year-olds.

Effects of maternal cigarette smoking during pregnancy on cognitive parameters of children and young adults: a literature review

The long term effects of maternal smoking during pregnancy on the cognitive development of the child are not well understood due to conflicting findings in past research. The aim of this paper was to provide an up to date, critical review of the literature to determine whether there is evidence of a relationship between tobacco smoke exposure in utero and cognitive functioning. We systematically reviewed observational studies (dated 2000-2011) that examined associations between tobacco smoke exposure in utero due to maternal smoking and performance on cognitive, intelligence, neurodevelopmental and academic tests. Eligible studies were identified through searches of Web of Knowledge, Medline, Science Direct, Google Scholar, CINAHL, EMBASE, Zetoc and Clinicaltrials.gov databases. The review found evidence of a relationship between tobacco smoke exposure in utero and reduced academic achievement and cognitive abilities independent of other variables. Maternal smoking during pregnancy may therefore be a modifiable risk factor for reduced cognitive abilities later in the life of the child. Giving up smoking during pregnancy should be initiated as early as possible to reduce the impact on the child's cognitive development.

Psychological differences between smokers who spontaneously quit during pregnancy and those who do not: a review of observational studies and directions for future research

INTRODUCTION

Although remarkable interindividual differences among pregnant smokers' decision/ability to quit have been documented, the psychological factors that may account for these differences have received less attention and comprised the primary aim of this review.

METHODS

We searched the medical and behavioral sciences literature from 1996 to November 2011 using PubMed and PsycINFO(®). Fifty-one articles were identified based on titles or abstracts. These articles were reviewed in full and searched for quantitative observational studies of population-based or clinical samples, with the main topic of comparing smokers who quit spontaneously during pregnancy with those who did not, utilizing multivariable analyses.

RESULTS

The eight pertinent studies reviewed herein included four longitudinal studies and four cross-sectional analyses. Amidst significant variability among measures used, social support, depressive symptoms, and anxiety appeared unrelated to smoking cessation during pregnancy. Furthermore, when severity of nicotine dependence was controlled, maternal history of attention-deficit/hyperactivity disorder, depression, bipolar disorder, and schizophrenia all showed no independent relationship with smoking cessation during pregnancy, whereas maternal history of conduct disorder did. Secure attachment, prosocial personality, self-esteem, and perceived parenting competence were additional predictors of cessation during pregnancy.

CONCLUSIONS

A greater understanding of psychological factors that differentiate smokers who spontaneously quit during pregnancy from those who do not is crucial to the design of more effective prenatal smoking cessation interventions and also may elucidate causal mechanisms that underlie the well-established link between maternal smoking during pregnancy and offspring behavioral problems. Directions for future research and public health and policy implications are discussed.

A longitudinal study on the effects of maternal smoking and secondhand smoke exposure during pregnancy on neonatal neurobehavior

Maternal smoking during pregnancy is one of the most modifiable causes of morbidity and mortality for both pregnant women and their fetuses. The long-term effects of prenatal exposure to smoke on child behavior and development have been the subject of more extensive research than have the short-term effects. Therefore, the aim of this work is to examine the effects of smoke exposure during pregnancy on neonatal behavior, including in our study a group of mothers exposed to secondhand smoke. The behavior of 282 healthy full-term newborns was assessed using the Neonatal Behavior Assessment Scale (NBAS) at 48-72 h of life. Sixty-two mothers smoked during pregnancy (no mother smoked more than 15 cig/day) and 17 were exposed to secondhand smoke. After adjusting for socio-demographic and obstetric factors, both newborns whose mothers smoked and those whose mothers were exposed to secondhand smoke showed significantly lower scores in the habituation cluster than non-smoking mothers. Exposure to secondhand smoke was also related to lower motor system cluster scores as well as some supplementary items and the newborns of smoking mothers showed significantly lower scores in the state regulation cluster and in some items of the state organization cluster than the newborns of non-smoking mothers. We conclude that active and passive smoking during pregnancy affects several aspects of neurobehavioral development, regardless of socio-demographic, obstetric and pediatric factors.

The impact of intrauterine tobacco exposure on the cerebral mass of the neonate based on the measurement of head circumference

The objective of the study was to assess cerebral mass, based on head circumference measurements in neonates exposed to tobacco smoke in utero, and to determine the relative proportions of the cerebral and body mass. The study included 147 neonates born in the period 2003-2004 at the Princess Anna Mazowiecka University Hospital and admitted to the Neonatal and Intensive Care Department of the Medical University in Warsaw. Subjects were divided into three groups on the basis of maternal status as active, passive, or nonsmokers determined by maternal urinary cotinine concentration and a questionnaire. Neonates whose mothers were active smokers throughout the whole period of pregnancy had a lower head circumference and in consequence a lower cerebral mass significantly more frequently when compared with those whose mothers were nonsmokers, P= 0.002. (Median difference in cerebral mass was 48.27 g.) The risk of lower cerebral mass was 3.9 (1.4-10.8, CI 95%) in the group of neonates whose mothers actively smoked cigarettes during pregnancy. A negative correlation was seen between cerebral mass and maternal urinary cotinine concentration (correlation coefficient r=-23, P= 0.006). The ratio of the cerebral to body mass was similar for neonates in all three groups. Active smoking during pregnancy had a negative effect on the cerebral mass of the neonate, however no such effect was observed in neonates whose mothers were passive smokers. The deficiency in cerebral mass increased with greater smoking intensity. Active smoking by the mother during pregnancy inhibits the growth of the brain as well as that of the body mass of the neonate.

Maternal smoking during pregnancy and anger temperament among adult offspring

Maternal smoking during pregnancy has been consistently associated with aggressive behaviors among offspring across the life course. We posit that anger, as a precedent of aggression, may have mediated the association. The current study examines the relation between maternal smoking during pregnancy and anger proneness among the adult offspring. Participants were 611 adult offspring (ages 38-48 years) of mothers enrolled in the Collaborative Perinatal Project between 1959 and 1966 in Boston and Providence. Information on maternal smoking during pregnancy was collected during prenatal visits. Spielberger's trait anger scale was used to measure anger proneness which has two components: anger temperament and angry reaction. Results from the full sample analyses showed that offspring whose mother smoked one pack or more per day on average scored 1.7 higher in anger temperament T scores in comparison to offspring whose mother never smoked during pregnancy (β=1.7, 95% Confidence Interval (CI): 0.1, 3.2). The fixed effects analyses among siblings that accounted for more confounding found a greater effect of around one standard deviation increase in anger temperament T scores corresponding to maternal smoking of one pack or more (β=7.4, 95% CI: 0.5, 14.4). We did not observe an association of maternal smoking during pregnancy with offspring angry reaction or other negative emotions including anxiety and depression. We concluded that prenatal exposure to heavy cigarette smoke was associated with an increased level of anger temperament, a stable personality trait that may carry the influence of prenatal smoking through the life course.

Adverse effects of heavy prenatal maternal smoking on attentional control in children with ADHD

OBJECTIVE

Exposure to heavy maternal cigarette smoking in pregnancy and severe maternal psychosocial stress during pregnancy appear to be important risk factors for the development of ADHD. This study aimed to determine whether these perinatal risk factors were associated with neuropsychological deficits commonly seen in ADHD.

METHOD

We examined the effect of these two risk factors on measures of attentional control, motor inhibition, visual-motor integration, and fine motor coordination in a group of 81 children with ADHD, aged from 8 to 18 years. The neuropsychological battery included the Connors' Continuous Performance Test (CPT), the Stroop Color-Word Interference Test, the Beery Visual-Motor Integration Test, and the Purdue Pegboard Test.

RESULTS

Heavy maternal smoking during pregnancy was associated with slower reaction times (p < .002), and reaction time variability (p < .007) on the CPT.

CONCLUSIONS

This study suggests a persistent negative effect of heavy prenatal maternal smoking on attentional control in children with ADHD. Future studies should examine the neurobiological basis and determine the degree to which inherited genetic susceptibility factors contribute to this finding.

Is smoking in pregnancy an independent predictor of academic difficulties at 14years of age? A birth cohort study

BACKGROUND

Studies of the effects of maternal smoking during pregnancy have reported inconsistent findings in relation to measures of offspring cognitive functioning. Few studies, however, have examined learning outcomes in adolescents, as opposed to IQ.

AIM

To examine the association between maternal smoking during pregnancy and academic performance among adolescent offspring.

STUDY DESIGN

Population-based birth cohort study.

SUBJECTS

7223 mothers and children were enrolled in the Mater-University of Queensland Study of Pregnancy in Brisbane (Australia) from 1981 to 1984. Analyses were restricted to the 4294 mothers and children for whom all information was reported at 14-year follow-up.

OUTCOME MEASURES

Reports of academic performance of 14-year-old offspring in English, Science and Mathematics with different patterns of maternal smoking (never smoked, smoked before and/or after pregnancy but not during pregnancy, or smoked during pregnancy).

RESULTS

Low academic achievement was more common only in those whose mothers had smoked during pregnancy. Effect sizes were, however, small. The adjusted mean difference in total learning score for smoking before and/or after pregnancy but not during pregnancy, and for smoking during pregnancy were -0.18 (-0.58, 0.22) and -0.40 (-0.69, -0.12). Similarly, the adjusted odds ratios were 0.9 (0. 65, 1.24) and 1.35 (1.07, 1.70).

CONCLUSION

Maternal smoking during pregnancy is a preventable prenatal risk factor associated with small decrements in offspring academic performance that continue into adolescence.

Effects of maternal and paternal smoking on attentional control in children with and without ADHD

Maternal smoking during pregnancy is a risk factor for attention-deficit/hyperactivity disorder (ADHD), but data on its adverse effects on cognitive functioning are sparse and inconsistent. Since the effect of maternal smoking during pregnancy may be due to correlated genetic risk factors rather than being a pure environmental effect, we examined the effect of prenatal exposure to smoking on attentional control, taking into account the effects of both maternal and paternal smoking, and examined whether these effects were genetically mediated by parental genotypes. We further examined whether the effect of prenatal exposure to smoking on attentional control interacted with genotypes of the child. Participants were 79 children with ADHD, ascertained for the International Multi-centre ADHD Gene project (IMAGE), and 105 normal controls. Attentional control was assessed by a visual continuous performance task. Three genetic risk factors for ADHD (DRD4 7-repeat allele of the exon 3 variable number of tandem repeats (VNTR), DAT1 10/10 genotype of the VNTR located in the 3' untranslated region, and the DAT1 6/6 genotype of the intron 8 VNTR) were included in the analyses. Paternal smoking had a negative effect on attentional control in children with ADHD and this effect appeared to be mediated by genetic risk factors. The prenatal smoking effect did not interact with genotypes of the child. Maternal smoking had no main effect on attentional control, which may be due to lower smoking rates. This study suggests that the effects of paternal smoking on attentional control in children with ADHD should be considered a proxy for ADHD and/or smoking risk genes. Future studies should examine if the results can be generalized to other cognitive domains.

Early childhood aetiology of mental health problems: a longitudinal population-based study

BACKGROUND

Mental health problems comprise an international public health issue affecting up to 20% of children and show considerable stability. We aimed to identify child, parenting, and family predictors from infancy in the development of externalising and internalising behaviour problems by age 3 years.

METHODS

Design Longitudinal, population-based survey completed by primary caregivers when children were 7, 12, 18, 24 and 36 months old. Participants 733 children sequentially recruited at 6-7 months from routine well-child appointments (August-September 2004) across six socio-economically and culturally diverse government areas in Victoria, Australia; 589 (80%) retained at 3 years. Measures 7 months: sociodemographic characteristics, maternal mental health (Depression Anxiety Stress Scale (DASS)), substance misuse, home violence, social isolation, infant temperament; 12 months: partner relationship, parenting (Parent Behavior Checklist (PBC)); 18, 24 and 36 months: child behaviour (Child Behavior Checklist 1(1/2)-5 (CBCL)), PBC, DASS.

RESULTS

Sixty-nine percent of all families attending well-child clinics took part. The consistent and cumulative predictors of externalising behaviours were parent stress and harsh discipline. Predictors of internalising behaviours included small family size, parent distress, and parenting. Twenty-five percent of variation in early externalising behaviour and 17% of variation in early internalising behaviour was explained.

CONCLUSIONS

Effective and cost-efficient population approaches to preventing mental health problems early in childhood are urgently needed. Programmes must support parents in reducing personal stress as well as negative parenting practices.

Pre- and postnatal influences on preschool mental health: a large-scale cohort study

BACKGROUND

Methodological challenges such as confounding have made the study of the early determinants of mental health morbidity problematic. This study aims to address these challenges in investigating antenatal, perinatal and postnatal risk factors for the development of mental health problems in pre-school children in a cohort of Western Australian children.

METHODS

The Raine Study is a prospective cohort study of 2,868 live born children involving 2,979 pregnant women recruited at 18 weeks gestation. Children were followed up at age two and five years. The Child Behaviour Checklist (CBCL) was used to measure child mental health with clinical cut-points, including internalising (withdrawn/depressed) and externalising (aggressive/destructive) behaviours (n = 1707).

RESULTS

Multinomial logistic regression analysis showed that the significant risk factors for behaviour problems at age two were the maternal experience of multiple stress events in pregnancy (OR = 1.20, 95% CI = 1.06, 1.37), smoking during pregnancy (OR = 1.30, 95% CI = 1.06, 1.59) and maternal ethnicity (OR = 3.34, 95% CI = 1.61, 6.96). At age five the experience of multiple stress events (OR = 1.17, 95% CI = 1.08, 1.27), cigarette smoking (OR = 1.19, 95% CI = 1.03, 1.37), male gender (OR = 1.43, 95% CI = 1.02, 2.00), breastfeeding for a shorter time (OR = .97, 95% CI = .94, .99) and multiple baby blues symptoms (OR = 1.08, 95% CI = 1.02, 1.14) were significant predictors of mental health problems.

CONCLUSIONS

Early childhood mental health is significantly affected by prenatal events in addition to the child's later environment. Interventions targeting adverse prenatal, perinatal and postnatal influences can be expected to improve mental health outcomes for children in the early years.

Maternal smoking during pregnancy and children's cognitive and physical development: a causal risk factor?

There remains considerable debate regarding the effects of maternal smoking during pregnancy on children's growth and development. Evidence that exposure to maternal smoking during pregnancy is associated with numerous adverse outcomes is contradicted by research suggesting that these associations are spurious. The authors investigated the relation between maternal smoking during pregnancy and 14 developmental outcomes of children from birth through age 7 years, using data from the Collaborative Perinatal Project (1959-1974; n = 52,919). In addition to adjusting for potential confounders measured contemporaneously with maternal smoking, the authors fitted conditional fixed-effects models among siblings that controlled for unmeasured confounders. Results from the conditional analyses indicated a birth weight difference of -85.63 g associated with smoking of >or=20 cigarettes daily during pregnancy (95% confidence interval: -131.91, -39.34) and 2.73 times' higher odds of being overweight at age 7 years (95% confidence interval: 1.30, 5.71). However, the associations between maternal smoking and 12 other outcomes studied (including Apgar score, intelligence, academic achievement, conduct problems, and asthma) were entirely eliminated after adjustment for measured and unmeasured confounders. The authors conclude that the hypothesized effects of maternal smoking during pregnancy on these outcomes either are not present or are not distinguishable from a broader range of familial factors associated with maternal smoking.

Adolescent environmental tobacco smoke exposure predicts academic achievement test failure

PURPOSE

Research has linked prenatal tobacco exposure to neurocognitive and behavioral problems that can disrupt learning and school performance in childhood. Less is known about its effects on academic achievement in adolescence when controlling for known confounding factors (e.g., environmental tobacco smoke [ETS]). We hypothesized that prenatal tobacco exposure would decrease the likelihood of passing academic achievement tests taken at 16 and 18 years of age.

METHODS

This study was a longitudinal analysis of birth cohort data including 6,380 pregnant women and offspring from the 1958 National Child Development Study (NCDS). Academic pass/fail performance was measured on British standardized achievement tests ("Ordinary Level" [O-Level] and Advanced Level: [A-Level]). Prenatal tobacco exposure plus controlling variables (ETS, teen offspring smoking and gender, maternal age at pregnancy, maternal smoking before pregnancy, and socioeconomic status) were included in regression models predicting O- and A-Level test failure.

RESULTS

Significant predictors of test failure in the O-Level model included exposure to maternal (OR = 0.71, p < .0001) and paternal (OR = 0.70, p < .0001) ETS, as well as teen smoking, female gender, and lower SES. Prenatal tobacco exposure did not influence failure. Similar factors emerged in the A-Level model except that male gender contributed to likelihood of failure. Prenatal exposure remained nonsignificant.

CONCLUSIONS

Our model suggests that adolescent exposure to ETS, not prenatal tobacco exposure, predicted failure on both O- and A-Level achievement tests when controlling for other factors known to influence achievement. Although this study has limitations, results bolster growing evidence of academic-related ETS consequences in adolescence.

Social factors, psychopathology, and maternal smoking during pregnancy

We investigated the relative importance of sociodemographic factors and psychiatric disorders for smoking among 453 pregnant women in the National Epidemiological Survey on Alcohol and Related Conditions. Women with less than a high school education and those with current-year nicotine dependence had the highest risk of smoking (90.5%), compared with women with a college degree and without nicotine dependence (3.9%). More effective and accessible interventions for nicotine dependence among pregnant smokers are needed.

Understanding Unintentional Injury Risk in Young Children II. The Contribution of Caregiver Supervision, Child Attributes, and Parent Attributes

OBJECTIVE

To identify child and parent attributes that relate to caregiver supervision and examine how these factors influence child-injury risk.

METHODS

Mothers completed diary records about supervision of their young child (2-5 years) when at home. Standardized questionnaires provided information about child attributes, maternal attributes, and children's history of injuries.

RESULTS

Correlations revealed that child attributes and parent attributes related both to actual maternal supervision and child-injury scores. Regression analyses to predict injury scores revealed child-temperament factors alone predicted all levels of severity (minor, moderately severe, and medically attended), but parent supervision also contributed to predict medically attended injuries.

CONCLUSIONS

Both child and parent factors influenced caregiver's supervision of young children at home and related to child-injury risk. For medically attended injuries, child attributes and parent supervision both predicted risk, whereas for less serious injuries, child factors alone determined risk.